US11122632B2 - Method for adjusting size of contention window in wireless communication system, and communication device using method - Google Patents
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Definitions
- the present disclosure relates to wireless communication, and more particularly, to a method of adjusting a contention window size in a wireless communication system, and a communication device using the method.
- next generation radio access technology considering enhanced mobile broadband communication (eMBB), massive MTC (mMTC), ultrareliable and low latency communication (URLLC) is discussed.
- eMBB enhanced mobile broadband communication
- mMTC massive MTC
- URLLC ultrareliable and low latency communication
- This new technology may be called new radio access technology (new RAT or NR) in the present disclosure for convenience.
- an unlicensed band which is the same as a 2.4 gigahertz (GHz) band used generally by the legacy WiFi system or an unlicensed band which is the same as a 5 GHz and 60 GHz band getting new attention is considered to be utilized in traffic offloading.
- GHz gigahertz
- An eNB or UE of an LTE/NR system must also perform the LBT for signal transmission in the unlicensed band (for convenience, referred to as a U-band).
- a communication technique using the unlicensed band the NR requires a discussion on a beamforming technique using multiple antennas and a communication technique using a new unlicensed band considering a bandwidth part depending on bandwidth capability of the UE.
- the present disclosure provides a method of adjusting a contention window size in a wireless communication system, and a communication device using the method.
- a method for adjusting a contention window size of a user equipment (UE) in a wireless communication system comprises transmitting data to a base station (BS) through a frequency band in a bandwidth part of the UE, wherein the bandwidth part is one part of a carrier bandwidth configured to the UE; receiving feedback information for the data from the BS; and adjusting the contention window size of the UE based on the feedback information, wherein the contention window size is a range of a counter value used in a channel access procedure (CAP) as an operation in which the UE determines channel occupancy, wherein the bandwidth part overlaps with a plurality of CAP bandwidths which are bandwidths in which the UE performs the channel access procedure, and wherein, based on the frequency band in which the data is transmitted overlapping with the plurality of CAP bandwidths, the UE adjusts the contention window size for at least one of the plurality of CAP bandwidths, based on the feedback information.
- CAP channel access procedure
- the UE may adjust only the contention window size for a CAP bandwidth having a greatest proportion of a resource to which the data is allocated among the plurality of CAP bandwidths.
- the UE may adjust the contention window size for each of all of the plurality of CAP bandwidths in which the data overlaps.
- the UE may perform a channel access procedure for the bandwidth part, and the UE may switch to a different bandwidth part when the UE fails in the CAP operation for a specific time duration or for at least a specific count.
- the different bandwidth may be a pre-configured bandwidth part, a bandwidth part before switching, or an initial/default bandwidth part.
- the contention window size may be adjusted to a minimum value for all priority classes.
- the contention window size may be adjusted to a value used in a bandwidth part before switching.
- the contention window size may be adjusted to a value included in downlink control information (DCI) reporting a bandwidth part switching command.
- DCI downlink control information
- the contention window size may be adjusted to a value lower by one level than a value before switching among sizes allowed for all priority classes.
- the contention window size may be adjusted to a value previously used in a corresponding bandwidth part.
- the feedback information may comprise an uplink grant related to a hybrid automatic repeat request (HARQ) process identity (ID) used to transmit the data, if a new data indicator (NDI) of the feedback information is toggled, the contention window size may be adjusted to a minimum value for all priority classes, if the NDI of the feedback information is not toggled, the contention window size may be adjusted to a value one level higher with respect to all priority classes, and the contention window size to be adjusted may be the contention window size for a CAP bandwidth, having a greatest proportion of a resource to which the data is allocated among the plurality of CAP bandwidths.
- HARQ hybrid automatic repeat request
- ID hybrid automatic repeat request
- the counter value When the counter value is initially set, the counter value may be set to any value greater than or equal to 0 and less than or equal to the contention window size.
- the counter value may be adjusted by sensing a channel in the channel access procedure.
- a method for adjusting a contention window size of a base station (BS) in a wireless communication system comprises transmitting data to a user equipment (UE) through a frequency band in a bandwidth part of the UE, wherein the bandwidth part is one part of a carrier bandwidth configured for the UE; receiving feedback information regarding the data from the UE; and adjusting the contention window size of the BS, based on the feedback information, wherein the contention window size is in the range of a counter value used in a channel access procedure (CAP) as an operation in which the BS determines channel occupancy, wherein the bandwidth part of the UE overlaps with a plurality of CAP bandwidths which are bandwidths in which the BS performs the channel access procedure, and wherein, when the frequency band in which the data is transmitted overlaps with the plurality of CAP bandwidths, the BS adjusts the contention window size for at least one of the plurality of CAP bandwidths, based on the feedback information.
- CAP channel access procedure
- the BS may adjust only the contention window size for a CAP bandwidth having a greatest proportion of a resource to which the data is allocated among the plurality of CAP bandwidths.
- the BS may adjust the contention window size for each of all of the plurality of CAP bandwidths in which the data overlaps.
- a user equipment comprising a transceiver transmitting and receiving a radio signal; and a processor operatively coupled with the transceiver, wherein the processor is configured to transmit data to a base station (BS) through a frequency band in a bandwidth part of the UE, wherein the bandwidth part is one part of a carrier bandwidth configured to the UE; receive feedback information for the data from the BS; and adjust the contention window size of the UE based on the feedback information, wherein the contention window size is a range of a counter value used in a channel access procedure (CAP) as an operation in which the UE determines channel occupancy, wherein the bandwidth part overlaps with a plurality of CAP bandwidths which are bandwidths in which the UE performs the channel access procedure, and wherein, based on the frequency band in which the data is transmitted overlapping with the plurality of CAP bandwidths, the UE adjusts the contention window size for at least one of the plurality of CAP bandwidths, based on the feedback information.
- CAP channel access procedure
- a method of performing listen before talk (LBT) based on transmission for each bandwidth part and beam introduced in an NR system, a method of adjusting a contention window size, and a method of performing LBT considering a time gap between an LBT success timing and an actual transmission timing are proposed to enable more effective communication using an unlicensed band in the NR system.
- FIG. 1 shows a wireless communication system to which the present disclosure may be applied.
- FIG. 3 is a diagram showing a wireless protocol architecture for a control plane.
- FIG. 4 illustrates a system structure of a next generation radio access network (NG-RAN) to which NR is applied.
- NG-RAN next generation radio access network
- FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.
- FIG. 6 illustrates an example of a frame structure that may be applied in NR.
- FIG. 7 illustrates CORESET
- FIG. 8 is a diagram illustrating a difference between a related art control region and the CORESET in NR.
- FIG. 9 illustrates an example of a frame structure for new radio access technology.
- FIG. 10 is an abstract schematic diagram illustrating hybrid beamforming from the viewpoint of TXRUs and physical antennas.
- FIG. 11 illustrates the beam sweeping operation for a synchronization signal and system information in a downlink (DL) transmission procedure.
- FIG. 12 schematically shows LBT performed for each beam.
- FIG. 13 schematically shows PDSCH scheduling in a situation where a BWP configured for a UE is greater than an LBT bandwidth.
- FIG. 14 is a flowchart for a contention window size adjustment method of a BS according to an embodiment of the present disclosure.
- FIG. 15 is a flowchart for a contention window size adjustment method of a UE according to another embodiment of the present disclosure.
- FIG. 16 is for describing CWS adjustment based on NACK in unit of CBG.
- FIG. 17 is an example for illustrating CWS adjustment based on NACK in unit of CBG.
- FIG. 18 is for describing an example of applying the [Proposed Method #17].
- FIG. 19 is a block diagram showing components of a transmission device 1810 and a reception device 1820 which perform the present disclosure.
- FIG. 20 shows an example of a signal processing module structure in the transmission device 1810 .
- FIG. 21 shows another example of the signal processing module structure in the transmission device 1810 .
- FIG. 22 shows an example of a wireless communication device according to an implementation example of the present disclosure.
- FIG. 1 shows a wireless communication system to which the present disclosure may be applied.
- the wireless communication system may be referred to as an Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN) or a Long Term Evolution (LTE)/LTE-A system.
- E-UTRAN Evolved-UMTS Terrestrial Radio Access Network
- LTE Long Term Evolution
- LTE-A Long Term Evolution
- the E-UTRAN includes at least one base station (BS) 20 which provides a control plane and a user plane to a user equipment (UE) 10 .
- the UE 10 may be fixed or mobile, and may be referred to as another terminology, such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), a wireless device, etc.
- the BS 20 is generally a fixed station that communicates with the UE 10 and may be referred to as another terminology, such as an evolved node-B (eNB), a base transceiver system (BTS), an access point, etc.
- eNB evolved node-B
- BTS base transceiver system
- access point etc.
- the BSs 20 are interconnected by means of an X2 interface.
- the BSs 20 are also connected by means of an S1 interface to an evolved packet core (EPC) 30 , more specifically, to a mobility management entity (MME) through S1-MME and to a serving gateway (S-GW) through S1-U.
- EPC evolved packet core
- MME mobility management entity
- S-GW serving gateway
- the EPC 30 includes an MME, an S-GW, and a packet data network-gateway (P-GW).
- the MME has access information of the UE or capability information of the UE, and such information is generally used for mobility management of the UE.
- the S-GW is a gateway having an E-UTRAN as an end point.
- the P-GW is a gateway having a PDN as an end point.
- Layers of a radio interface protocol between the UE and the network can be classified into a first layer (L1), a second layer (L2), and a third layer (L3) based on the lower three layers of the open system interconnection (OSI) model that is well-known in the communication system.
- a physical (PHY) layer belonging to the first layer provides an information transfer service by using a physical channel
- a radio resource control (RRC) layer belonging to the third layer serves to control a radio resource between the UE and the network.
- the RRC layer exchanges an RRC message between the UE and the BS.
- FIG. 2 is a diagram showing a wireless protocol architecture for a user plane.
- FIG. 3 is a diagram showing a wireless protocol architecture for a control plane.
- the user plane is a protocol stack for user data transmission.
- the control plane is a protocol stack for control signal transmission.
- a PHY layer provides an upper layer with an information transfer service through a physical channel.
- the PHY layer is connected to a medium access control (MAC) layer which is an upper layer of the PHY layer through a transport channel.
- MAC medium access control
- Data is transferred between the MAC layer and the PHY layer through the transport channel.
- the transport channel is classified according to how and with what characteristics data is transferred through a radio interface.
- the physical channel may be modulated according to an Orthogonal Frequency Division Multiplexing (OFDM) scheme, and use the time and frequency as radio resources.
- OFDM Orthogonal Frequency Division Multiplexing
- the functions of the MAC layer include mapping between a logical channel and a transport channel and multiplexing and demultiplexing to a transport block that is provided through a physical channel on the transport channel of a MAC Service Data Unit (SDU) that belongs to a logical channel.
- SDU MAC Service Data Unit
- the MAC layer provides service to a Radio Link Control (RLC) layer through the logical channel.
- RLC Radio Link Control
- the functions of the RLC layer include the concatenation, segmentation, and reassembly of an RLC SDU.
- QoS Quality of Service
- RB Radio Bearer
- the RLC layer provides three types of operation mode: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM).
- TM Transparent Mode
- UM Unacknowledged Mode
- AM Acknowledged Mode
- AM RLC provides error correction through an Automatic Repeat Request (ARQ).
- ARQ Automatic Repeat Request
- the RRC layer is defined only on the control plane.
- the RRC layer is related to the configuration, reconfiguration, and release of radio bearers, and is responsible for control of logical channels, transport channels, and PHY channels.
- An RB means a logical route that is provided by the first layer (PHY layer) and the second layers (MAC layer, the RLC layer, and the PDCP layer) in order to transfer data between UE and a network.
- the function of a Packet Data Convergence Protocol (PDCP) layer on the user plane includes the transfer of user data and header compression and ciphering.
- the function of the PDCP layer on the user plane further includes the transfer and encryption/integrity protection of control plane data.
- PDCP Packet Data Convergence Protocol
- What an RB is configured means a process of defining the characteristics of a wireless protocol layer and channels in order to provide specific service and configuring each detailed parameter and operating method.
- An RB can be divided into two types of a Signaling RB (SRB) and a Data RB (DRB).
- SRB Signaling RB
- DRB Data RB
- the SRB is used as a passage through which an RRC message is transmitted on the control plane
- the DRB is used as a passage through which user data is transmitted on the user plane.
- the UE If RRC connection is established between the RRC layer of UE and the RRC layer of an E-UTRAN, the UE is in the RRC connected state. If not, the UE is in the RRC idle state.
- a downlink transport channel through which data is transmitted from a network to UE includes a broadcast channel (BCH) through which system information is transmitted and a downlink shared channel (SCH) through which user traffic or control messages are transmitted. Traffic or a control message for downlink multicast or broadcast service may be transmitted through the downlink SCH, or may be transmitted through an additional downlink multicast channel (MCH).
- BCH broadcast channel
- SCH downlink shared channel
- Traffic or a control message for downlink multicast or broadcast service may be transmitted through the downlink SCH, or may be transmitted through an additional downlink multicast channel (MCH).
- MCH downlink multicast channel
- an uplink transport channel through which data is transmitted from UE to a network includes a random access channel (RACH) through which an initial control message is transmitted and an uplink shared channel (SCH) through which user traffic or control messages are transmitted.
- RACH random access channel
- SCH uplink shared channel
- Logical channels that are placed over the transport channel and that are mapped to the transport channel include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast traffic channel (MTCH).
- BCCH broadcast control channel
- PCCH paging control channel
- CCCH common control channel
- MCCH multicast control channel
- MTCH multicast traffic channel
- the physical channel includes several OFDM symbols in the time domain and several subcarriers in the frequency domain.
- One subframe includes a plurality of OFDM symbols in the time domain.
- An RB is a resources allocation unit, and includes a plurality of OFDM symbols and a plurality of subcarriers.
- each subframe may use specific subcarriers of specific OFDM symbols (e.g., the first OFDM symbol) of the corresponding subframe for a physical downlink control channel (PDCCH), that is, an L1/L2 control channel.
- PDCCH physical downlink control channel
- a Transmission Time Interval (TTI) is a unit time for subframe transmission.
- new radio access technology new RAT, NR
- next generation radio access technology considering enhanced mobile broadband communication (eMBB), massive MTC (mMTC), ultrareliable and low latency communication (URLLC) is discussed.
- eMBB enhanced mobile broadband communication
- mMTC massive MTC
- URLLC ultrareliable and low latency communication
- This new technology may be called new radio access technology (new RAT or NR) in the present disclosure for convenience.
- FIG. 4 illustrates a system structure of a next generation radio access network (NG-RAN) to which NR is applied.
- NG-RAN next generation radio access network
- the NG-RAN may include a gNB and/or an eNB that provides user plane and control plane protocol termination to a terminal.
- FIG. 4 illustrates the case of including only gNBs.
- the gNB and the eNB are connected by an Xn interface.
- the gNB and the eNB are connected to a 5G core network (5GC) via an NG interface.
- 5GC 5G core network
- the gNB and the eNB are connected to an access and mobility management function (AMF) via an NG-C interface and connected to a user plane function (UPF) via an NG-U interface.
- AMF access and mobility management function
- UPF user plane function
- FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.
- the gNB may provide functions such as an inter-cell radio resource management (Inter Cell RRM), radio bearer management (RB control), connection mobility control, radio admission control, measurement configuration & provision, dynamic resource allocation, and the like.
- the AMF may provide functions such as NAS security, idle state mobility handling, and so on.
- the UPF may provide functions such as mobility anchoring, PDU processing, and the like.
- the SMF may provide functions such as UE IP address assignment, PDU session control, and so on.
- FIG. 6 illustrates an example of a frame structure that may be applied in NR.
- a frame may be composed of 10 milliseconds (ms) and include 10 subframes each composed of 1 ms.
- One or a plurality of slots may be included in a subframe according to subcarrier spacings.
- the following table 1 illustrates a subcarrier spacing configuration ⁇ .
- the following table 2 illustrates the number of slots in a frame (N frame, ⁇ slot ), the number of slots in a subframe (N subframe, ⁇ slot ), the number of symbols in a slot (N slot symb ), and the like, according to subcarrier spacing configurations ⁇ .
- a physical downlink control channel may include one or more control channel elements (CCEs) as illustrated in the following table 3.
- CCEs control channel elements
- the PDCCH may be transmitted through a resource including 1, 2, 4, 8, or 16 CCEs.
- the CCE includes six resource element groups (REGs), and one REG includes one resource block in a frequency domain and one orthogonal frequency division multiplexing (OFDM) symbol in a time domain.
- REGs resource element groups
- OFDM orthogonal frequency division multiplexing
- a new unit called a control resource set may be introduced.
- the terminal may receive the PDCCH in the CORESET.
- FIG. 7 illustrates CORESET
- the CORESET includes N CORESET RB number of resource blocks in the frequency domain, and N CORESET symb ⁇ 1, 2, 3 ⁇ number of symbols in the time domain.
- N CORESET RB and N CORESET symb may be provided by a base station via higher layer signaling.
- a plurality of CCEs (or REGs) may be included in the CORESET.
- the UE may attempt to detect a PDCCH in units of 1, 2, 4, 8, or 16 CCEs in the CORESET.
- PDCCH candidates One or a plurality of CCEs in which PDCCH detection may be attempted may be referred to as PDCCH candidates.
- a plurality of CORESETs may be configured for the terminal.
- FIG. 8 is a diagram illustrating a difference between a related art control region and the CORESET in NR.
- a control region 800 in the related art wireless communication system (e.g., LTE/LTE-A) is configured over the entire system band used by a base station (BS). All the terminals, excluding some (e.g., eMTC/NB-IoT terminal) supporting only a narrow band, must be able to receive wireless signals of the entire system band of the BS in order to properly receive/decode control information transmitted by the BS.
- BS base station
- CORESETs 801 , 802 , and 803 are radio resources for control information to be received by the terminal and may use only a portion, rather than the entirety of the system bandwidth.
- the BS may allocate the CORESET to each UE and may transmit control information through the allocated CORESET. For example, in FIG. 8 , a first CORESET 801 may be allocated to UE 1 , a second CORESET 802 may be allocated to UE 2 , and a third CORESET 803 may be allocated to UE 3 .
- the terminal may receive control information from the BS, without necessarily receiving the entire system band.
- the CORESET may include a UE-specific CORESET for transmitting UE-specific control information and a common CORESET for transmitting control information common to all UEs.
- NR may require high reliability according to applications.
- a target block error rate (BLER) for downlink control information (DCI) transmitted through a downlink control channel may remarkably decrease compared to those of conventional technologies.
- BLER target block error rate
- content included in DCI can be reduced and/or the amount of resources used for DCI transmission can be increased.
- resources can include at least one of resources in the time domain, resources in the frequency domain, resources in the code domain and resources in the spatial domain.
- FIG. 9 illustrates an example of a frame structure for new radio access technology.
- a structure in which a control channel and a data channel are time-division-multiplexed within one TTI, as shown in FIG. 9 can be considered as a frame structure in order to minimize latency.
- a shaded region represents a downlink control region and a black region represents an uplink control region.
- the remaining region may be used for downlink (DL) data transmission or uplink (UL) data transmission.
- DL transmission and UL transmission are sequentially performed within one subframe and thus DL data can be transmitted and UL ACK/NACK can be received within the subframe. Consequently, a time required from occurrence of a data transmission error to data retransmission is reduced, thereby minimizing latency in final data transmission.
- a time gap for a base station and a terminal to switch from a transmission mode to a reception mode or from the reception mode to the transmission mode may be required.
- some OFDM symbols at a time when DL switches to UL may be set to a guard period (GP) in the self-contained subframe structure.
- Wavelengths are shortened in millimeter wave (mmW) and thus a large number of antenna elements can be installed in the same area. That is, the wavelength is 1 cm at 30 GHz and thus a total of 100 antenna elements can be installed in the form of a 2-dimensional array at an interval of 0.5 lambda (wavelength) in a panel of 5 ⁇ 5 cm. Accordingly, it is possible to increase a beamforming (BF) gain using a large number of antenna elements to increase coverage or improve throughput in mmW.
- BF beamforming
- TXRU transceiver unit
- independent beamforming per frequency resource can be performed.
- installation of TXRUs for all of about 100 antenna elements decreases effectiveness in terms of cost. Accordingly, a method of mapping a large number of antenna elements to one TXRU and controlling a beam direction using an analog phase shifter is considered.
- Such analog beamforming can form only one beam direction in all bands and thus cannot provide frequency selective beamforming.
- Hybrid beamforming (BF) having a number B of TXRUs which is smaller than Q antenna elements can be considered as an intermediate form of digital BF and analog BF.
- the number of directions of beams which can be simultaneously transmitted are limited to B although it depends on a method of connecting the B TXRUs and the Q antenna elements.
- hybrid beamforming which is a combination of digital beamforming and analog beamforming is emerging.
- analog beamforming or RF beamforming
- an RF end performs precoding (or combining) and thus it is possible to achieve the performance similar to digital beamforming while reducing the number of RF chains and the number of D/A (or A/D) converters.
- the hybrid beamforming structure may be represented by N TXRUs and M physical antennas.
- the digital beamforming for the L data layers to be transmitted at the transmitting end may be represented by an N by L matrix, and the converted N digital signals are converted into analog signals via TXRUs, and analog beamforming represented by an M by N matrix is applied.
- FIG. 10 is an abstract schematic diagram illustrating hybrid beamforming from the viewpoint of TXRUs and physical antennas.
- the number of digital beams is L and the number of analog beams is N.
- the base station by designing the base station to change the analog beamforming in units of symbols, it is considered to support more efficient beamforming for a terminal located in a specific area.
- N TXRUs and M RF antennas as one antenna panel in FIG. 7 , it is considered to introduce a plurality of antenna panels to which independent hybrid beamforming is applicable in the NR system.
- analog beams suitable to receive signals may be different for terminals and thus a beam sweeping operation of sweeping a plurality of analog beams to be applied by a base station per symbol in a specific subframe (SF) for at least a synchronization signal, system information and paging such that all terminals can have reception opportunities is considered.
- SF subframe
- FIG. 11 illustrates the beam sweeping operation for a synchronization signal and system information in a downlink (DL) transmission procedure.
- a physical broadcast channel a physical broadcast channel
- analog beams belonging to different antenna panels can be simultaneously transmitted within one symbol, and a method of introducing a beam reference signal (BRS) which is a reference signal (RS) to which a single analog beam (corresponding to a specific antenna panel) is applied in order to measure a channel per analog beam, as illustrated in FIG. 8 , is under discussion.
- the BRS can be defined for a plurality of antenna ports, and each antenna port of the BRS can correspond to a single analog beam.
- all analog beams in an analog beam group are applied to the synchronization signal or xPBCH and then the synchronization signal or xPBCH is transmitted such that an arbitrary terminal can successively receive the synchronization signal or xPBCH.
- An NR system may support up to 400 megahertz (MHz) for each one component carrier (CC). If a UE operating in such a wideband CC operates always in a state where RF is powered on for the entire CC, battery consumption of the UE may increase. Alternatively, considering multiple use cases (e.g., eMBB, URLLC, mMTC, etc.) operating in one wideband CC, different numerologies (e.g., sub-carrier spacing (SCS)) may be supported for different frequency bands in the CC. Alternatively, each UE may have different capability for a maximum bandwidth. In this regard, a BS may indicate to the UE that an operation is to be performed only in a partial bandwidth, not the entire bandwidth of the wideband CC.
- SCS sub-carrier spacing
- the partial bandwidth is defined as a bandwidth part (BWP).
- the BWP may consist of resource blocks (RBs) consecutive on a frequency axis, and may correspond to one numerology (e.g., an SCS, a cyclic prefix (CP) length, a slot/mini-slot duration, etc.).
- numerology e.g., an SCS, a cyclic prefix (CP) length, a slot/mini-slot duration, etc.
- the BS may configure a plurality of BWPs in one CC configured for the UE. For example, a BWP occupying a relatively small frequency domain may be configured in a PDCCH monitoring slot, and a PDSCH indicated in a PDCCH may be scheduled on a BWP greater than that.
- another BWP may be configured for some of the UEs.
- BWPs at both sides may be configured in the same slot by excluding some center spectra from the entire bandwidth considering frequency domain inter-cell interference cancellation between adjacent cells. That is, the BS may configure at least one DL/UL BWP for the UE associated with the wideband CC.
- At least one DL/UL BWP among DL/UL BWP(s) configured at a specific timing may be activated (by L1 signaling or MAC CE or RRC signaling or the like). Switching to another configured DL/UL BWP may be indicated (by L1 signaling or MAC CE or RRC signaling or the like). Switching to a predetermined DL/UL BWP may occur upon expiration of a timer value according to a timer.
- an activated DL/UL BWP is defined as an active DL/UL BWP.
- the UE may not receive a configuration for the DL/UL BWP.
- a DL/UL BWP assumed by the UE in such a situation is defined as an initial active DL/UL BWP.
- LAA licensed-assisted access
- An eNB operating LAA Scell(s) shall perform the channel access procedures described in this sub clause for accessing the channel(s) on which the LAA Scell(s) transmission(s) are performed.
- the eNB may transmit a transmission including PDSCH/PDCCH/EPDCCH on a carrier on which LAA Scell(s) transmission(s) are performed, after first sensing the channel to be idle during the slot durations of a defer duration T d ; and after the counter N is zero in step 4.
- the counter N is adjusted by sensing the channel for additional slot duration(s) according to the steps below:
- N init N init , where N init is a random number uniformly distributed between 0 and CW P , and go to step 4;
- step 3 sense the channel for an additional slot duration, and if the additional slot duration is idle, go to step 4; else, go to step 5;
- the eNB may transmit a transmission including PDSCH/PDCCH/EPDCCH on the carrier, if the channel is sensed to be idle at least in a slot duration T sl when the eNB is ready to transmit PDSCH/PDCCH/EPDCCH and if the channel has been sensed to be idle during all the slot durations of a defer duration T d immediately before this transmission.
- the eNB proceeds to step 1 after sensing the channel to be idle during the slot durations of a defer duration T d .
- a slot duration T sl is considered to be idle if the eNB senses the channel during the slot duration, and the power detected by the eNB for at least 4 us within the slot duration is less than energy detection threshold X Thresh . Otherwise, the slot duration T sl is considered to be busy.
- CW min,p ⁇ CW p ⁇ CW maxp,p is the contention window.
- CW p adjustment is described in contention window adjustment procedure.
- CW min,p and CW max,p are chosen before step 1 of the procedure above.
- m p , CW min,p , and CW max,p are based on channel access priority class associated with the eNB transmission, as shown in Table 4.
- the eNB shall not decrement N during the slot duration(s) overlapping with discovery signal transmission.
- the eNB shall not continuously transmit on a carrier on which the LAA Scell(s) transmission(s) are performed, for a period exceeding T mcot,p as given in Table 4.
- Table 4 is a table for a channel access priority class.
- the channel is considered to be idle for T drs if it is sensed to be idle during the slot durations of T drs .
- the eNB transmits transmissions including PDSCH that are associated with channel access priority class p on a carrier, the eNB maintains the contention window value CW p and adjusts CW p before step 1 of the aforementioned procedure for those transmissions using the following steps:
- Reference subframe k is the starting subframe of the most recent transmission on the carrier made by the eNB, for which at least some HARQ-ACK feedback is expected to be available.
- the eNB shall adjust the value of CW p for every priority class p ⁇ 1, 2, 3, 4 ⁇ based on a given reference subframe k only once.
- the eNB transmits transmissions including PDCCH/EPDCCH with DCI format 0A/0B/4A/4B and not including PDSCH that are associated with channel access priority class p on a channel starting from time t 0 , the eNB maintains the contention window value CW p and adjusts CW p before step 1 of the procedure described in sub clause 15.1.1 for those transmissions using the following steps:
- step 2 2) if less than 10% of the UL transport blocks scheduled by the eNB using Type 2 channel access procedure in the time interval between t 0 and t 0 +T CO have been received successfully, increase CW p for every priority class p ⁇ 1, 2, 3, 4 ⁇ to the next higher allowed value and remain in step 2; otherwise, go to step 1.
- CW p CW max,p is consecutively used K times for generation of N init .
- K is selected by eNB from the set of values ⁇ 1, 2, . . . , 8 ⁇ for each priority class p ⁇ 1, 2, 3, 4 ⁇ .
- An eNB accessing a carrier on which LAA Scell(s) transmission(s) are performed shall set the energy detection threshold (X Thresh ) to be less than or equal to the maximum energy detection threshold X Thresh_max .
- X Thresh_max is determined as follows:
- X Thresh_max min ⁇ ⁇ T max + 10 ⁇ ⁇ dB , X r ⁇
- X Thres_max max ⁇ ⁇ - 72 + 10 ⁇ log ⁇ ⁇ 10 ⁇ ( BWMHz / 20 ⁇ ⁇ MHz ) ⁇ ⁇ dBm , min ⁇ ⁇ T max , T max - T A + ( P H + 10 ⁇ log ⁇ ⁇ 10 ⁇ ( BWMHz / 20 ⁇ ⁇ MHz ) - P TX ) ⁇ ⁇ ⁇
- An eNB can access multiple carriers on which LAA Scell(s) transmission(s) are performed, according to one of the Type A or Type B procedures to be described later.
- N c i The counter N described in the aforementioned channel access procedure for transmission(s) including PDSCH/PDCCH/EPDCCH is determined for each carrier c i and is denoted as N c i .
- N c i is maintained according to Type A1 or Type A2.
- Counter N as described in the aforementioned channel access procedure for transmission(s) including PDSCH/PDCCH/EPDCCH is independently determined for each carrier c i and is denoted as N c i .
- the eNB when the eNB ceases transmission on any one carrier c j ⁇ C, for each carrier c i ⁇ c j , the eNB can resume decrementing N c i when idle slots are detected either after waiting for a duration of 4 ⁇ T sl , or after reinitialising N c i .
- Counter N is determined as described in the aforementioned channel access procedure for transmission(s) including PDSCH/PDCCH/EPDCCH for carrier c j ⁇ C, and is denoted as N c j , where c j is the carrier that has the largest CW p value.
- N c i N c j .
- a carrier c j ⁇ C is selected by the eNB as follows:
- the eNB shall not continuously transmit on a carrier c i ⁇ c j , c i ⁇ C, for a period exceeding T mcot,p as given in Table 4, where the value of T mcot,p is determined using the channel access parameters used for carrier c j .
- a single CW p value is maintained for the set of carriers C.
- step 2 of the aforementioned contention window adjustment procedure is modified as follows:
- a CW p value is maintained independently for each carrier c i ⁇ C using the aforementioned contention window adjustment procedure.
- CW p value of carrier c j1 ⁇ C is used, where c j1 is the carrier with largest CW p among all carriers in set C.
- a UE and a eNB scheduling UL transmission(s) for the UE shall perform the procedures described below for the UE to access the channel(s) on which the LAA Scell(s) transmission(s) are performed.
- the UE can access a carrier on which LAA Scell(s) UL transmission(s) are performed according to one of Type 1 or Type 2 UL channel access procedures.
- an UL grant scheduling a PUSCH transmission indicates Type 1 channel access procedure
- the UE shall use Type 1 channel access procedure for transmitting transmissions including the PUSCH transmission unless stated otherwise below.
- Type 2 channel access procedure the UE shall use Type 2 channel access procedure for transmitting transmissions including the PUSCH transmission unless stated otherwise below.
- the UE shall use Type 1 channel access procedure for transmitting SRS transmissions not including a PUSCH transmission.
- Table 5 is for a channel access priority class for uplink.
- the UE scheduled to transmit transmissions including PUSCH in a set subframes n 0 , n 1 , . . . , n w ⁇ 1 using PDCCH DCI Format 0B/4B and if the UE cannot access the channel for a transmission in subframe n k , the UE shall attempt to make a transmission in subframe n k+1 according to the channel access type indicated in the DCI, where k ⁇ 0, 1, . . . w ⁇ 2 ⁇ , and w is the number of scheduled subframes indicated in the DCI.
- the UE may continue transmission in subframes after n k where k ⁇ 0, 1, . . . w ⁇ 1 ⁇ .
- the UE is not expected to be indicated with different channel access types for the transmissions in those subframes.
- the UE may transmit in a later subframe n k2 , k2 ⁇ 1, . . . w ⁇ 1 ⁇ using Type 2 channel access procedure.
- the UE may transmit in a later subframe n k2 , k2 ⁇ 1, . . . w ⁇ 1 ⁇ using Type 1 channel access procedure with the UL channel access priority class indicated in the DCI corresponding to subframe n k2 .
- the UE receives an UL grant and the DCI indicates a PUSCH transmission starting in subframe ⁇ i using Type 1 channel access procedure, and if the UE has an ongoing Type 1 channel access procedure before subframe ⁇ i .
- the UE is scheduled to transmit on a set of carriers C in subframe ⁇ i , and if the UL grants scheduling PUSCH transmissions on the set of carriers C indicate Type 1 channel access procedure, and if the same ‘PUSCH starting position’ is indicated for all carriers in the set of carriers C, and if the carrier frequencies of set of carriers C is a subset of one of the predefined sets of carrier frequencies,
- the eNB shall schedule UL transmissions between t 0 and t 0 +T CO in contiguous subframes if they can be scheduled contiguously.
- the UE may use Type 2 channel access procedure for the UL transmission.
- the eNB indicates Type 2 channel access procedure for the UE in the DCI, the eNB indicates the channel access priority class used to obtain access to the channel in the DCI.
- the UE may transmit the transmission using Type 1 channel access procedure after first sensing the channel to be idle during the slot durations of a defer duration T d ; and after the counter N is zero in step 4.
- the counter N is adjusted by sensing the channel for additional slot duration(s) according to the steps described below.
- N init N init , where N init is a random number uniformly distributed between 0 and CW p , and go to step 4;
- step 3 sense the channel for an additional slot duration, and if the additional slot duration is idle, go to step 4; else, go to step 5;
- the UE may transmit a transmission including PUSCH on the carrier, if the channel is sensed to be idle at least in a slot duration T sl when the UE is ready to transmit the transmission including PUSCH, and if the channel has been sensed to be idle during all the slot durations of a defer duration T d immediately before the transmission including PUSCH.
- the UE proceeds to step 1 after sensing the channel to be idle during the slot durations of a defer duration T d .
- a slot duration T sl is considered to be idle if the UE senses the channel during the slot duration, and the power detected by the UE for at least 4 us within the slot duration is less than energy detection threshold X Thresh . Otherwise, the slot duration T sl is considered to be busy.
- CW p (CW min,p ⁇ CW p ⁇ CW max,p ) is a contention window. Applying of CW p is described in a contention window adjustment procedure to be described below.
- CW min,p and CW max,p are chosen before step 1 of the procedure above.
- m p , CW min,p , and CW max,p are based on the channel access priority class signaled to the UE as shown in Table 5.
- the channel is considered to be idle for T short_ul if it is sensed to be idle during the slot durations of T short_ul .
- the UE transmits transmissions using Type 1 channel access procedure that are associated with channel access priority class p on a carrier, the UE maintains the contention window value CW p and adjusts CW p for those transmissions before step 1 of the aforementioned Type 1 uplink channel access procedure, using the following procedure:
- HARQ_ID_ref is the HARQ process ID of UL-SCH in reference subframe n ref .
- the reference subframe n ref is determined as follows:
- the UE may keep the value of CW p unchanged for every priority class p ⁇ 1, 2, 3, 4 ⁇ , if the UE scheduled to transmit transmissions without gaps including PUSCH in a set subframes n 0 , n 1 , . . . , n w ⁇ 1 using Type 1 channel access procedure, and if the UE is not able to transmit any transmission including PUSCH in the set of subframes.
- the UE may keep the value of CW p for every priority class p ⁇ 1, 2, 3, 4 ⁇ the same as that for the last scheduled transmission including PUSCH using Type 1 channel access procedure, if the reference subframe for the last scheduled transmission is also n ref .
- CW p CW max,p is consecutively used K times for generation of N init .
- K is selected by UE from the set of values ⁇ 1, 2, . . . , 8 ⁇ for each priority class p ⁇ 1, 2, 3, 4 ⁇ .
- a UE accessing a carrier on which LAA Scell(s) transmission(s) are performed shall set the energy detection threshold (X Thresh ) to be less than or equal to the maximum energy detection threshold X Thresh_max .
- X Thresh_max is determined as follows:
- X Thresh_max ′ min ⁇ ⁇ T max + 10 ⁇ ⁇ dB , X r ⁇
- X Thres_max ′ max ⁇ ⁇ - 72 + 10 ⁇ log ⁇ ⁇ 10 ⁇ ( BWMHz / 20 ⁇ ⁇ MHz ) ⁇ ⁇ dBm , min ⁇ ⁇ T max , T max - T A + ( P H + 10 ⁇ log ⁇ ⁇ 10 ⁇ ( BWMHz / 20 ⁇ ⁇ MHz ) - P TX ) ⁇ ⁇ ⁇ ⁇
- the present disclosure proposes a multi-beam based listen-before-talk method and a contention window size adjustment scheme, when a transmission node performs a channel access procedure in a wireless communication system including a base station (BS) and a user equipment (UE) in an unlicensed band.
- BS base station
- UE user equipment
- an unlicensed band which is the same as a 2.4 gigahertz (GHz) band used generally by the legacy WiFi system or an unlicensed band which is the same as a 5 GHz and 60 GHz band getting new attention is considered to be utilized in traffic offloading.
- GHz gigahertz
- An eNB or UE of an LTE/NR system must also perform the LBT for signal transmission in the unlicensed band (for convenience, referred to as a U-band). Further, when the eNB or UE of the LTE/NR system transmits a signal, another communication node such as WiFi or the like must also perform the CCA to prevent interference.
- a CCA threshold is defined as ⁇ 62 dBm as to a non-WiFi signal and is defined as ⁇ 82 dBm as to a WiFi signal. This means that an STA or an AP does not transmit a signal to prevent interference, for example, when a signal other than the WiFi signal is received with power greater than or equal to ⁇ 62 dBm.
- a multi-beam operation may also be utilized in an NR U-band, similarly to a case where a plurality of antenna elements are used in millimeter wave (mmW) of NR to increase a beamforming (BF) gain, thereby increasing coverage or increasing a throughput.
- mmW millimeter wave
- BF beamforming
- a multi-beam LBT operation shall be performed first before a transmission node performs transmission.
- LBT methods may be different when transmission is performed while performing beam sweeping on multiple analog beams and when transmission is performed by fixing the beams as a single analog beam.
- NR is a system in which UEs having various bandwidth capabilities coexist.
- a UE capable of performing transmission/reception through the entire carrier bandwidth in the entire carrier bandwidth and a UE supporting only a partial bandwidth in the carrier bandwidth may coexist.
- a subset consisting of a part of a physical resource block (PRB) consecutive in the carrier bandwidth is referred to as a bandwidth part (BWP).
- BWP bandwidth part
- the UE performs transmission/reception only with an active BWP among the configured BWP at a specific timing, and does not expect to receive a PDSCH, a PDCCH, a CSI-RS, a TRS, or the like in a region other than the active BWP.
- NACK for a PDSCH scheduled to a plurality of BS LBT BWPs in an overlap/overlaid manner in one slot needs to be properly calculated by considering a BWP of the UE and the LBT bandwidth of the BS, thereby adjusting the CWS when NACK of at least a specific ratio occurs.
- a PDSCH across two BS LBT bandwidths may be scheduled through a BWP of the UE in one slot.
- the BS shall determine which one of the LBT bandwidth 1 and the LBT bandwidth 2 will be considered for NACK to adjust the CWS.
- the present disclosure proposes an LBT method for a case where transmission is performed while sweeping several analog beams when a channel is occupied after LBT is performed and the occupied channel is used for transmission, and an LBT method for a case where transmission is performed while fixing to a single analog beam.
- the present disclosure proposes a method of adjusting a CWS for each LBT bandwidth when UEs having different BWP capabilities coexist and a PDSCH is scheduled by overlapping with a plurality of LBT bandwidths of the BS.
- a physical broadcast channel implies a physical channel transmitting basic system information (hereinafter, MIB (master information block) such as a system band, SFN (system frame number), or the like.
- MIB master information block
- SFN system frame number
- RMSI recovery minimum system information
- OSI other system information
- SS synchronization signal
- DM-RS demodulation reference signal
- a slot implies a basic time unit consisting of a plurality of OFDM symbols.
- a beamforming technique utilizing multiple antennas in an NR system is also considered in an NR U-band as one of essential parts.
- listen-before-talk shall be performed for fair coexistence with a Wi-Fi device or the like which previously exists on a corresponding band before a transmission node transmits data or the like (before performing medium access).
- LBT listen-before-talk
- the following multi-beam LBT methods may be considered.
- the transmission node may operate by selecting one of the following three methods.
- a UE may operate when one of the three methods is signaled from a BS.
- the method (1) is a method of performing omni-direction LBT other than a specific direction, even if transmission in a specific beam direction is introduced in NR.
- the omni-direction is divided into four different beam directions (e.g., a beam direction 1, a beam direction 2, a beam direction 3, a beam direction 4), and LBT is performed for each of the different beam directions.
- the transmission node may perform transmission only for the beam direction 1 and the beam direction 3.
- transmission on all beam directions may not be performed.
- the transmission node may perform LBT only for the beam direction 1, the beam direction 2, and the beam direction 3.
- the transmission node may perform transmission only for the beam direction 1 and the beam direction 3.
- an LBT slot duration may be a value (e.g., 4 T) greater than the LBT time T required for each beam.
- the [Proposed Method #1] considers a relationship between the omni-directional LBT and the directional LBT as a method in which a product of a time required to perform the directional LBT for each direction and the total number of directions split for the omni-direction is set to be similar or equal to a time required to perform the omni-directional LBT.
- an index of a beam to be transmitted in practice may have to be dynamically indicated to a reception node since transmission is performed only in a beam direction in which directional LBT succeeds.
- the transmission node may report information on the beam direction to a reception node in a beam direction in which LBT succeeds, so that the reception node can more easily recognize the beam direction in which LBT succeeds, thereby more smoothly performing a reception operation related to the beam direction.
- the beam direction may be replaced with a resource region scheduled to be transmitted, and the SRS resource implies a time-frequency resource on which a BS indications SRS transmission.
- a sequence A and/or a frequency resource 1 are transmitted when LBT succeeds in all beam directions
- a sequence B and/or a frequency resource 2 are transmitted when LBT succeeds in the beam directions #1 and #2 or the beam directions #2 and #3 or the beam directions #1 and #3
- a sequence C and/or a frequency resource 3 are transmitted when LBT succeeds only in one direction out of the three directions.
- a sequence may be configured differently for all cases obtained from the LBT result. Therefore, when a corresponding SRS resource is transmitted in a beam direction in which LBT succeeds according to a directional LBT result, a reception node may know information on a beam direction in which LBT succeeds in practice.
- a beam of a specific direction in which LBT fails may be produced while performing directional LBT.
- the following methods may be considered as a detailed operation of multi-beam LBT.
- FIG. 12 schematically shows LBT performed for each beam.
- FIG. 12 shows an example for a case where there are three beams, i.e., a beam A, a beam B, and a beam C.
- FIG. 12( a ) shows a transmission procedure for each beam after LBT is normally performed for each beam when LBT succeeds for all beams
- FIG. 12( b ) shows a transmission procedure when LBT fails for the beam A.
- the transmission procedure performed after the normal LBT is an operation in which the directional LBT is performed sequentially from the beam A to the beam C as shown in FIG. 12( a ) and thereafter transmission is performed for each beam in the same order.
- the LBT may be performed with a delay corresponding to a time required for signal transmission when the LBT in the direction of the beam A succeeds instead of immediately performing the LBT for a next beam, i.e., the beam B, as shown in FIG. 12( b ) .
- a specific node fails in LBT for the beam A and succeeds in LBT for the beams B and C
- transmission for beams in which LBT succeeds is delayed during a transmission time duration for the beam A after LBT is performed on all beams as shown in FIG. 12( a ) (i.e., if transmission for the beam A is not performed during the transmission time duration for the beam A shown in FIG. 12( a ) )
- another node may success in LBT and thus be able to transmit a signal during the time duration. Therefore, even if the specific node succeeds in LBT for the beams B and C and thus transmits a signal thereof, interference may occur due to the signal transmission of another node.
- the specific node which has performed the LBT during a time duration in which signal transmission is delayed may not perform any operation.
- the beams may be paired so that each of two beams are set as one group.
- the [Proposed method #4] may be applied not to an individual beam but to a group beam to perform directional LBT.
- next LBT may be performed on the group beam by being temporarily delayed by a transmission time.
- a signal may be transmitted only in a group beam direction in which LBT succeeds.
- each of beam directions in the aforementioned [Proposed Method #1] to [Proposed Method #4] may be applied by being configured as a beam group.
- a back-off counter may be individually set for each beam direction.
- the back-off counter of the existing beam direction A may be held temporarily and the LBT may be performed in another beam direction.
- the held counter value may be increased by a predetermined or agreed specific value.
- a penalty may be added. The penalty may start from the same value as the counter value which starts to decrease or which is held, and may additionally start to decrease the counter only in an idle state during a specific time.
- the [Proposed Method #6] proposes a method of configuring an individual per-beam random back-off counter for each beam direction by considering a per-beam operation introduced in NR in the existing LBT scheme based on the random back-off counter, and configuring and changing the per-beam random back-off counter when the per-beam LBT operation is performed.
- PDCCH and PDSCH Not applicable, when Channel access excluding exceptions of priority class is the following note selected depending on multiplexed data. Note: initial/random access, mobility, paging, transmission of only reference signals, and transmission of only PDCCH (e.g., RACH message 4), handover command, GC-PDCCH, or applicability of LBT scheme other than cat. 4 regarding short message paging-related control messages transmitted alone or multiplexed with DRS
- the existing wide beam LBT is a method of performing LBT one time omni-directionally or in a specific direction and thereafter performing transmission in a corresponding direction when the LBT succeeds
- the proposed method is a method of performing LBT based on random back-off such as DL data or the like when the LBT is performed.
- a CWS may be set to be smaller than that of narrow beam LBT, or an LBT slot duration may be set to be short, or a CCA threshold may be increased, so that a time required until medium access (MA) is performed is set to be relatively small.
- the proposed method is also applicable to an uplink such as an SRS or the like.
- a method applied to a beam management SRS may be considered as a representative example thereof.
- the existing LBT methods include a type-1 method which is an LBT method based on a random back-off counter and a type-2 method which is an LBT method performed without the random back-off counter.
- a transmission signal is transmitted by including a PDSCH in the transmission signal
- the type-2 method the transmission signal is transmitted without including the PDSCH. That is, the type-2 method is used when non-unicast data is transmitted.
- the type-1 method may also be referred to as category 4 (or cat. 4) LBT
- the type-2 method may also be referred to as category 2 LBT (or cat. 2).
- the [Proposed Method #7] considers the use of the LBT method based on the random back-off counter rather than the type-2 method even if non-unicast data is transmitted.
- whether to apply the LBT method based on the random back-off counter may vary depending on a type or configuration of the non-unicast data.
- the existing method when performing omni-directional LBT, if the measured energy value is P, the existing method performs transmission by comparing the measured energy value P and the CCA threshold value T and by considering that a channel is idle only when P ⁇ T. However, this method may determine that a channel is idle if P*R ⁇ T as a result of scaling the measured energy value P with a ratio R (where R is a rational number satisfying 0 ⁇ R ⁇ 1) of a beam to be transmitted in all directions, or may determine that the channel is idle if P ⁇ T/R as a result of scaling the CCA threshold value.
- Scaling based on a ratio of a beam is considered in this method when the measured power/energy value and the threshold are compared by considering fairness with the omni-directional LBT in case of introducing the directional LBT.
- the existing LAA includes a CWS adjustment method.
- bandwidth capability of UEs is up to 20 MHz, which is the same as an LBT bandwidth of a BS.
- DL downlink
- a PDSCH for 10 UEs is scheduled in a first slot of a DL burst.
- At least 8 NACKs are reported from the UEs, so that LBT is performed again by increasing a CWS when an NACK ratio is greater than or equal to 80%.
- a UE capable of performing transmission/reception by using the entire carrier bandwidth (up to about 400 MHz) according to bandwidth capability of the UE may coexist with UEs capable of performing transmission/reception only through a subset (e.g., BWP) having a bandwidth smaller than a carrier bandwidth.
- a subset e.g., BWP
- FIG. 13 schematically shows PDSCH scheduling in a situation where a BWP configured for a UE is greater than an LBT bandwidth.
- FIG. 13 schematically shows LBT bandwidths (BWs) 1 and 2 of a gNB and a BWP of a UE.
- BWs LBT bandwidths
- two LBT BWs 1 and 2 may overlap with one BWP of the UE.
- each of the LBT BWs 1 and 2 may be 20 MHz.
- the BWP of the UE may be 40 MHz.
- FIG. 13 schematically shows a situation where a PDSCH 1 and a PDSCH 2 are allocated.
- the PDSCH 1 is allocated across an LBT BW 1 and an LBT BW 2
- the PDSCH 2 is allocated only to the LBT BW 2 .
- the UE which has a BW corresponding to a value obtained by adding the LBT BW 1 and LBT BW 2 of the gNB as a BWP may be configured by fully overlapping with the two LBT BWs of the gNB, and a PDSCH across the two gNB LBT BWs may be scheduled.
- a NACK ratio which is a criterion for CWS adjustment of the LBT BW 1 and LBT BW 2 of the gNB may be calculated by the following proposed methods.
- all PDSCHs scheduled to a BWP of a UE are considered for a NACK ratio to adjust a CWS.
- all PDSCHs, i.e., both the PDSCH 1 and the PDSCH 2 , scheduled to the BWP of the UE are considered for NACK counting of the LBT BW 1 and the LBT BW 2 so as to contribute to an increase in a CWS when greater than or equal to a specific NACK ratio.
- NACK of the PDSCH is considered when a CWS of a corresponding LBT BW is adjusted.
- NACK of the PDSCH 2 may be considered only for CWS adjustment of the LBT BW 2 .
- a decoding result of the PDSCH 1 is NACK, it may be considered for both the two LBT BWs and thus be used in CWS adjustment.
- all resources scheduled for the PDSCH 1 may be allocated with a ratio of 40% for the LBT BW 1 , and may be allocated with a ratio of 60% for the LBT BW 2 .
- the decoding result may be considered for CWS adjustment for each BW by considering a 40:60 ratio which is a ratio of resources allocated to the LBT BW 1 and the LBT BW 2 , or the decoding result may be considered only for CWS adjustment for the LBT BW 2 having a higher ratio of allocated resources.
- This method relates to how to apply a PUSCH transmission result to CWS adjustment of each of the LBT BWs 1 and 2 of the UE, when the UE transmits a UL burst by succeeding in LBT in each LBT BW in a situation where a DL BW of the UE of FIG. 13 is changed to a UL BW, a PDSCH is changed to a PUSCH, and LBT BWs 1 and 2 of the gNB are changed to LBT BWs 1 and 2 of the UE. That is, the aforementioned methods may also equally apply to an uplink.
- a CWS is adjusted by considering a PUSCH transmission result, i.e., NACK, for each of the LBT BWs 1 and 2 when the UL BW of the UE overlaps with the LBT BW of the UE as in the [Proposed Method #9].
- a CWS is adjusted by considering a transmission result for an LBT BW thereof when a corresponding PUSCH transmission resource is scheduled in a specific LBT BW, based on a resource scheduled for a PUSCH of a UE, as in the [Proposed Method #10].
- a PUSCH transmission result for a case where PUSCH transmission resources are scheduled across both the two LBT BWs of the UE may be considered for CWS adjustment of the two LBT BWs, or may be considered only for CWS of an LBT BW having a greater proportion of a PUSCH resource.
- the gNB may activate at least one DL/UL BWP (through L1 signaling or MAC CE or RRC signaling or the like) among configured DL/UL BWP(s) at a specific timing for the UE. Further, switching to another configured DL/UL BWP may be indicated (through L1 signaling or MAC CE or RRC signaling or the like) or switching to a determined DL/UL BWP may be achieved at the expiry of a timer value based on a timer. As such, when the DL/UL BWP is switched, a maximum CWS and/or back-off counter value applied to a BWP before switching or a BWP after switching may be reset or maintained.
- the CWS and back-off counter value of the UE may be adjusted according to the following options.
- the priority class may be the channel access priority classes of Table 4 and Table 5. Specifically, taking the channel access priority class of Table 4 for example, if the channel access priority class is 3, a CWS for a switched BWP may be reset to 15 which is the minimum value among ⁇ 15, 31, 63 ⁇ .
- the option 3 is for a method in which a CWS for a BWP after switching is indicated together, while indicating switching of the BWP through DCI.
- the channel access priority class of Table 4 for example as described above, if the channel access priority class is 3 for specific data and a CWS for a BWP before switching has a size of 31, according to the option 4, if the channel access priority class is 3, a CWS for a BWP after switching is 15 which is a CWS one step before. Further, according to the option 5, if the channel access priority class is 3, then 31 is directly used.
- the specific time or count may be a timer-based value or a pre-configured value
- the DL/UL LBT may be performed at a corresponding BWP by switching to a pre-agreed or configured specific BWP.
- the pre-agreed or configured BWP may be a BWP before switching or an initial/default BWP.
- a CWS value may be adjusted as in the [Proposed Method #12].
- a gNB indicates to a UE the BWP switching and PUSCH transmission for uplink at the switched BWP but the UE fails in LBT at the switched BWP and thus fails in PUSCH transmission
- the UE may switch to a pre-agreed or configured specific BWP, and may adjust a CWS value as in the [Proposed Method #12].
- the pre-agreed or configured BWP may be a BWP before switching or an initial/default BWP.
- the gNB may recognize without ambiguity whether the UE has not succeeded in LBT or has not received a switching indication of the BWP.
- FIG. 14 is a flowchart for a contention window size adjustment method of a BS according to an embodiment of the present disclosure.
- the BS may include the aforementioned eNB or gNB.
- the BS transmits data to a UE through a frequency band in a bandwidth part of the UE (S 1410 ).
- the bandwidth part may be one part of a carrier bandwidth configured for the UE.
- the BS receives feedback information on the data from the UE (S 1420 ).
- the BS adjusts the contention window size of the BS, based on the feedback information (S 1430 ).
- the contention window size may be in the range of a counter value used in a channel access procedure (CAP) as an operation in which the BS determines channel occupancy.
- CAP channel access procedure
- the bandwidth part may overlap with a plurality of CAP bandwidths in which the BS performs the CAP.
- a detailed example thereof may be the same as shown in FIG. 13 .
- FIG. 13 shows only an example in which two CAP bandwidths of the BS overlap with a bandwidth part of a UE, it is also possible that one CAP bandwidth of the BS overlaps with the bandwidth part of the UE.
- the CAP bandwidth of the BS may have the same size as the bandwidth part.
- three or more CAP bandwidths of the BS may overlap with the bandwidth part of the UE.
- the BS may adjust a contention window size for at least one of the plurality of CAP bandwidths, based on the feedback information.
- the contention window size may be adjusted for all of a plurality of overlapping CAP bandwidths as in the [Proposed Method #9]. Further, the contention window size may be adjusted only for a CAP bandwidth in which relatively more resources are allocated/included for the data.
- FIG. 15 is a flowchart for a contention window size adjustment method of a UE according to another embodiment of the present disclosure.
- the UE transmits data to a BS through a frequency band in a bandwidth part of the UE (S 1510 ).
- the bandwidth part may be one part of a carrier bandwidth configured for the UE.
- the UE receives feedback information on the data from the BS (S 1520 ).
- the UE adjusts the contention window size of the UE, based on the feedback information (S 1530 ).
- the contention window size may be in the range of a counter value used in a channel access procedure (CAP) as an operation in which the BS determines channel occupancy.
- CAP channel access procedure
- the bandwidth part may overlap with a plurality of CAP bandwidths in which the UE performs the CAP.
- a detailed example thereof may be the same as that described in the [Proposed Method #11].
- FIG. 13 and the [Proposed Method #11] show only an example in which two CAP bandwidths of the UE overlap with a bandwidth part of the UE, it is also possible that one CAP bandwidth of the UE overlaps with the bandwidth part of the UE.
- the CAP bandwidth of the UE may have the same size as the bandwidth part.
- three or more CAP bandwidths of the UE may overlap with the bandwidth part of the UE.
- the UE may adjust a contention window size for at least one of the plurality of CAP bandwidths, based on the feedback information.
- FIG. 14 and FIG. 15 relate to a contention window size adjustment of a BS and a UE, respectively.
- each of the aforementioned [Proposed Method #9] to [Proposed Method #13] is written based on any one of a UE perspective and a BS perspective, the proposed methods may be applied to both the BS and the UE.
- the CAP and CAP bandwidth described in FIG. 14 and FIG. 15 may have the same meaning as listen before talk (LBT) and an LBT bandwidth, respectively.
- a bandwidth of a BWP configured for a BS or a UE in an unlicensed band may be at least 20 MHz.
- LBT shall succeed, and a bandwidth in which LBT is performed may be multiplies of 20 MHz, i.e., 20 MHz*N (where N is a natural number).
- a transmission node may delay transmission until LBT succeeds for the entire bandwidth or may perform transmission only with the partial bandwidth in which LBT succeeds.
- An RF chain may be changed in a process in which the transmission node changes a transmission bandwidth, or an additional operation may be necessary to satisfy a requirement such as in-band/out-of-band emission and/or frequency domain spectral mask or the like according to an actual transmission bandwidth.
- LBT LBT which allows a transmission attempt upon determining that a channel is idle after performing LBT during a specific time (e.g., 25 us).
- LBT may be performed with multiples of 20 MHz, i.e., 20 MHz*N (where N is a natural number).
- the proposed method may apply only for a case where a time required when the transmission node changes the transmission bandwidth is greater than or equal to a specific time.
- a time required to change the transmission bandwidth may vary depending on UE or gNB capability.
- the time required to the change may vary depending on a relationship between the entire bandwidth and the transmission bandwidth (for example, when a size between the entire bandwidth and the transmission bandwidth is greater than or equal to a threshold).
- the requirement such as the change in the operating bandwidth of the RF chain may cause the time gap between the actual transmission timing and the LBT success timing.
- a channel may suddenly become a busy state by neighboring another node when transmission is performed after a corresponding time. Therefore, short LBT may be performed again to start transmission only when confirming that the channel is idle.
- a BW of a BWP is 80 MHz
- 4 LBT BWs in unit of 20 MHz are BW #1, BW #2, BW #3, and BW #4 in an ascending order of frequency
- 20 MHz-unit LBT succeeds for the BW #1 and the BW #2 and fails for the BW #4.
- a transmission node may re-configure a transmission bandwidth to 40 MHz, and may perform short LBT in unit of 20 MHz again for the BW #1 and the BW #2 before starting transmission at the re-configured bandwidth. Transmission may start upon confirming that a channel is idle.
- the specific node may not be able to perform transmission even if LBT succeeds. Therefore, the specific node performs short LBT again to guarantee accuracy regarding whether the specific node performs transmission according to a result of the short LBT.
- a transmission bandwidth may be adjusted again hierarchically with the partial bandwidth (i.e., BW #Y) and transmission may start after short LBT is performed.
- BW #Y an LBT result of the BW #Y shows that a channel is in a busy state
- 4 LBT may be performed again from the beginning by updating (or reusing) a CWS used in first LBT of a previous BW #X with respect to a bandwidth (i.e., BW #X) at which the first LBT succeeds. More generally, upon determining that even the partial bandwidth BW #X at which LBT succeeds out of the entire bandwidth is busy after short LBT, it may operate to perform Cat. 4 LBT again. At this time, a bandwidth in which LBT is performed may be the entire bandwidth or may be a transmission node implementation issue. In this case, LBT may be performed by updating (or reusing) a CWS when performing the first LBT.
- a transmission bandwidth may be re-configured again to the BW #1, and transmission may start upon confirming that a channel is idle after performing short LBT.
- Cat. 4 LBT may start again by updating (or reusing) the existing CWS at the entire bandwidth of 80 MHz.
- An exemplary embodiment in which the gap is required even in the middle of transmission may be a method of performing LBT by applying the proposed method during a time gap, which occurs when changing to a sub-band RF band after a corresponding duration while performing transmission (in the meantime, preparing for signal processing involved in the RF change) by maintaining a wideband RF bandwidth without an RF change for an initial specific duration (e.g., X-symbol or 1-slot), and subsequently performing the remaining transmission.
- an initial specific duration e.g., X-symbol or 1-slot
- CWS adjustment method based on HARQ-ACK corresponding to a PDSCH overlapping with one or more LBT bandwidths when the LBT bandwidth is defined as a basic frequency-axis resource unit at which a BS adjusts CWS (in this case, HARQ-ACK may imply CBG-unit HARQ-ACK in which (re)transmission in unit of code block group (CBG) is configured).
- FIG. 16 is for describing CWS adjustment based on NACK in unit of CBG.
- an LBT BW 1 and LBT BW 2 of a gNB are shown, and a PDSCH 1 is scheduled across the LBT BW 1 and the LBT BW 2 , and a PDSCH 2 is scheduled only for the LBT BW 2 .
- a CWS adjustment method for the PDSCH 1 may be a problem.
- a CWS adjustment method based on NACK in unit of CBG may be considered.
- NACK of all CBGs in one transport block may be considered as one NACK, and CWS adjustment based thereon may be considered.
- the following options may be considered when a specific CBG in a scheduled PDSCH overlaps with a plurality of LBT bandwidths.
- the CBG 1 and the CBG 4 are included in an LBT BW 1
- the CBG 3 and the CBG 6 are included in the LBT BW 2
- the CBG 2 and the CBG 5 are across the LBT BW 1 and the LBT BW 2 .
- NACK for each of the CBG 2 and the CBG 5 may be used in CWS adjustment for both the LBT BW 1 and the LBT BW 2 .
- NACK for the CBG 2 and the CBG 5 may be used only in CWS adjustment for the LBT BW 2 to which resources are allocated with a higher ratio.
- a case where a BS schedules a PDSCH that can overlap with a plurality of LBT BWs may be considered when the BS is configured with a BWP for performing LBT in unit of 20 MHz such as the LBT BW 1 and the LBT BW 2 , and a bandwidth of a BWP of the UE includes two LBT BWs of the BS.
- the PDSCH 1 and the PDSCH 2 may respectively include 6 CBGs and 2 CBGs. If each of CBGs scheduled for a first slot of a DL burst (hereinafter, a reference DL resource) exits only within one LBT BW of the BS, HARQ-ACK feedback information for a corresponding CBG may be applied only for CWS adjustment of an LBT BW including the CBG.
- a reference DL resource HARQ-ACK feedback information for a corresponding CBG may be applied only for CWS adjustment of an LBT BW including the CBG.
- HARQ-ACK for the CBGs 1 and 4 constituting the PDSCH 1 is used in CWS adjustment of the LBT BW 1 and CBGs 3 and 6 of the PDSCH 1 and CBGs 1 and 2 of the PDSCH 2 are included in the LBT BW 2
- HARQ-ACK of corresponding CBGs may be used only in CWS adjustment of an LBT BW thereof.
- CWS adjustment may be performed as in the proposed method (1) or (2).
- the following options may be considered when a specific CBG in a scheduled PUSCH overlaps with a plurality of LBT bandwidths.
- the reference LBT bandwidth may be configured or indicated through a dynamic control signal (e.g., DCI) or a higher layer signal (e.g., RRC signaling) of a BS, or may be used in CWS adjustment of an LBT bandwidth having a greater proportion of an uplink (UL) resource among LBT bandwidths scheduled for a CBG indicated to be transmitted.
- a dynamic control signal e.g., DCI
- a higher layer signal e.g., RRC signaling
- the aforementioned method may be applicable under the premise that, when a BS fails in reception of specific CBG(s), retransmission of CBG(s) is always indicated in next retransmission scheduling.
- This principle may be applied to time-advanced CBG index(es) of all slots or to a first slot of a UL burst considered by the BS.
- FIG. 17 is an example for illustrating CWS adjustment based on NACK in unit of CBG.
- new data may be scheduled by sending a UL grant to a UE after 3 ms or 4 ms or retransmission of some or all CBGs constituting the PUSCH 1 may be indicated.
- a CWS of each LBT BW may be adjusted as in the [Proposed Method #16] according to the decoding result of the PUSCH 1 .
- CBGs scheduled for corresponding retransmission may be assumed to be NACK, and the UE may perform CBW adjustment of an LBT BW scheduled for a corresponding CBG.
- CWS adjustment for each LBT BW of the UE if a CBG in which retransmission is indicated is scheduled only for a specific LBT BW as in the [Proposed Method #4], the CWS adjustment may be applied only to the LBT bandwidth. If the CBG overlaps with two LBT BWs, it may be used for CWS adjustment of both of the two LBT BWs or may be used only for CWS adjustment of an LBT BW having a greater proportion of a UL resource.
- the PUSCH 1 may be successfully decoded.
- ACK may be assumed, and a CWS of each LBT BW may be initialized.
- NR supports a wider bandwidth operation. Therefore, a wideband (>20 MHz) may be divided into a plurality of sub-bands in unit of 20 MHz so that LBT is performed and CWS adjustment/management is achieved in each sub-band.
- LBT may be performed and CWS may be managed in unit of 20 MHz by selecting a specific representative carrier.
- FIG. 18 is for describing an example of applying the [Proposed Method #17].
- a sub-band LBT e.g., 20 MHz
- a wideband LBT >20 MHz
- the BWP 3 includes the BWP 0 and the BWP 1
- the BWP 4 includes the BWP 1 and the BWP 2
- the BWP 5 includes the remaining parts.
- a result obtained by performing sub-band LBT in unit of 20 MHz may be considered for CWS adjustment of a corresponding BWP, and may also be considered for CWS adjustment of a BWP (e.g., the BWP 3 including the BWP 0 , and the BWP 5 ) including the corresponding BWP. Accordingly, when the CWS is updated to a value one level higher in the BWP 0 , the CWS of the BWP 3 and the BWP 5 is also updated to a value one level higher.
- LBT may be performed with a previously updated CWS.
- the CWS of the BWP 0 and/or the BWP 1 may be initialized together according to a configuration or may not be initialized.
- the present disclosure is not limited to direct communication between UEs but is also applicable in an uplink or a downlink.
- a BS or a relay node or the like may use the proposed method.
- Examples for the aforementioned proposed scheme can be included as one of implementation methods of the present disclosure, and thus can be apparently regarded as a sort of proposed methods.
- the aforementioned proposed schemes can be independently implemented, it is also possible to be implemented by combining (or merging) some proposed schemes.
- a rule may be defined such that information on whether to apply the proposed methods (or information on rules of the proposed methods) is reported by a BS to a UE or by a transmitting UE to a receiving UE through a pre-defined signal (e.g., a physical layer signal or a higher layer signal).
- FIG. 19 is a block diagram showing components of a transmission device 1810 and a reception device 1820 which perform the present disclosure.
- each of the transmission device and the reception device may be a BS or a UE.
- the transmission device 1810 and the reception device 1820 may respectively include transceivers 1812 and 1822 capable of transmitting or receiving radio signals carrying information and/or data, signals, messages, and the like, memories 1813 and 1823 storing various types of information related to communication in a wireless communication system, and processors 1811 and 1821 connected to components such as the transceivers 1812 and 1822 and the memories 1813 and 1823 and configured to control the memories 1813 and 1823 and/or the transceivers 1812 and 1822 such that the corresponding devices perform at least one of the aforementioned embodiments of the present disclosure.
- a transmitter/receiver may be called a transceiver.
- the memories 1813 and 1823 may store programs for processing and control of the processors 1811 and 1821 and temporarily store input/output information.
- the memories 1813 and 1823 may be used as buffers.
- the processors 1811 and 1821 generally control overall operations of various modules in the transmission device and the reception device. Particularly, the processors 1811 and 1821 may execute various control functions for performing the present disclosure.
- the processors 1811 and 1821 may also be called controllers, microcontrollers, microprocessors, microcomputers, and the like.
- the processors 1811 and 1821 may be implemented by hardware, firmware, software or a combination thereof. When the present disclosure is implemented using hardware, ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), or the like configured to perform the present disclosure may be included in the processors 1811 and 1821 .
- ASICs application specific integrated circuits
- DSPs digital signal processors
- DSPDs digital signal processing devices
- PLDs programmable logic devices
- FPGAs field programmable gate arrays
- firmware or software may be configured to include modules, procedures, functions, or the like which perform functions or operations of the present disclosure, and the firmware or software configured to perform the present disclosure may be included in the processors 1811 and 1821 or stored in the memories 1813 and 1823 and driven by the processors 1811 and 1821 .
- the processor 1811 of the transmission device 1810 may perform predetermined coding and modulation on a signal and/or data which will be transmitted to the outside and then transmit the coded and modulated signal or data to the transceiver 1812 .
- the processor 1811 may generate a codeword by performing demultiplexing, channel coding, scrambling, and modulation on a data string to be transmitted.
- the codeword may include information equivalent to transport blocks that are data blocks provided by a MAC layer.
- One transport block (TB) may be coded into one codeword.
- Each codeword may be transmitted to the reception device through one or more layers.
- the transceiver 1812 may include an oscillator.
- the transceiver 1812 may include one or a plurality of transmission antennas.
- a signal processing procedure of the reception device 1820 may be reverse to the signal processing procedure of the transmission device 1810 .
- the transceiver 1822 of the reception device 1820 may receive radio signals transmitted from the transmission device 1810 under the control of the processor 1821 .
- the transceiver 1822 may include one or a plurality of reception antennas.
- the transceiver 1822 may restore each signal received through the reception antenna to a baseband signal by performing frequency down-conversion.
- the transceiver 1822 may include an oscillator for frequency down-conversion.
- the processor 1821 may restore data intended to be transmitted by the transmission device 1810 by performing decoding and demodulation on radio signals received through the reception antenna.
- the transceivers 1812 and 1822 may include one or a plurality of antennas.
- the antennas may serve to transmit signals processed by the transceivers 1812 and 1822 to the outside or receive external radio signals and transmit the radio signals to the transceivers 1812 and 1822 according to an embodiment under the control of the processors 1811 and 1821 .
- the antennas may also be called antenna ports.
- Each antenna may correspond to one physical antenna or may be configured by a combination of two or more physical antennas. A signal transmitted from each antenna cannot be decomposed any more by the reception device 1820 .
- a reference signal (RS) transmitted in association with an antenna defines the antenna from a perspective of the reception device 1820 and enables the reception device 1820 to perform channel estimation for the antenna irrespective of whether a channel is a single radio channel from a physical antenna or a composite channel from a plurality of physical antenna elements including the antenna. That is, an antenna may be defined such that a channel carrying symbols on the antenna can be derived from a channel carrying other symbols on the same antenna.
- a transceiver which supports a multi-input multi-output (MIMO) function for transmitting/receiving data using a plurality of antennas may be connected to two or more antennas.
- MIMO multi-input multi-output
- FIG. 20 shows an example of a signal processing module structure in the transmission device 1810 .
- signal processing may be performed by a processor of a BS/UE such as the processors 1811 and 1821 of FIG. 20 .
- the transmission device 1810 in the UE or the BS may include a scrambler 301 , a modulator 302 , a layer mapper 303 , an antenna port mapper 304 , a resource block mapper 305 and a signal generator 306 .
- the transmission device 1810 may transmit one or more codewords. Coded bits in each codeword are scrambled by the scrambler 301 and transmitted on a physical channel.
- a codeword may also be referred to as a data string and may be equivalent to a transport block that is a data block provided by a MAC layer.
- the scrambled bits are modulated into complex-valued modulation symbols by the modulator 302 .
- the modulator 302 may modulate the scrambled bits according to a modulation scheme and arrange the scrambled bits as complex-valued symbols representing positions on a signal constellation.
- the modulation scheme is not limited, and m-phase shift keying (m-PSK) or m-quadrature amplitude modulation (m-QAM) may be used to module the coded data.
- m-PSK m-phase shift keying
- m-QAM m-quadrature amplitude modulation
- the modulator may also be referred to as a modulation mapper.
- the complex-valued modulation symbols may be mapped to one or more transport layers by the layer mapper 303 .
- the complex-valued modulation symbols on the layers may be mapped by the antenna port mapper 304 for transmission on antenna ports.
- the resource block mapper 305 may map complex-valued modulation symbols for respective antenna ports to appropriate resource elements in a virtual resource block allocated for transmission.
- the resource block mapper may map the virtual resource block to a physical resource block according to an appropriate mapping scheme.
- the resource block mapper 305 may allocate the complex-valued modulation symbols for the respective antenna ports to appropriate subcarriers and multiplex the same according to a user.
- the signal generator 306 may modulate the complex-valued modulation symbols for the respective antenna ports, that is, antenna-specific symbols according to a specific modulation scheme, for example, orthogonal frequency division multiplexing (OFDM) to generate a complex-valued time domain OFDM symbol signal.
- the signal generator may perform inverse fast Fourier transform (IFFT) on the antenna-specific symbols, and a cyclic prefix (CP) may be inserted into time domain symbols on which IFFT has been performed. OFDM symbols are subjected to digital-to-analog conversion, frequency up-conversion, and the like and transmitted to a reception device through respective transmission antennas.
- the signal generator may include an IFFT module, a CP insertion device, a digital-to-analog converter (DAC), a frequency uplink converter, and the like.
- FIG. 21 shows another example of the signal processing module structure in the transmission device 1810 .
- signal processing may be performed by a processor of a UE/BS such as the processors 1811 and 1821 of FIG. 19 .
- the transmission device 1810 in the UE or the BS may include a scrambler 401 , a modulator 402 , a layer mapper 403 , a precoder 404 , a resource block mapper 405 , and a signal generator 406 .
- the transmission device 1810 may scramble coded bits in the codeword through the scrambler 401 and then transmit the scrambled bits through a physical channel.
- the scrambled bits are modulated into complex-valued modulation symbols by the modulator 402 .
- the modulator may modulate the scrambled bits according to a predetermined modulation scheme and arrange the scrambled bits as complex-valued symbols representing positions on a signal constellation.
- the modulation scheme is not limited, and pi/2-binary phase shift keying (pi/2-BPSK), m-phase shift keying (m-PSK) or m-quadrature amplitude modulation (m-QAM) may be used to modulate the coded data.
- the complex-valued modulation symbols may be mapped to one or more transport layers by the layer mapper 403 .
- the complex-valued modulation symbols on the layers may be precoded by the precoder 404 for transmission through antenna ports.
- the precoder may perform precoding after performing transform precoding for the complex-valued modulation symbols.
- the precoder may perform precoding without performing transform precoding.
- the precoder 404 may process the complex-valued modulation symbols according to MIMO using multiple transmission antennas to output antenna-specific symbols and distribute the antenna-specific symbols to the corresponding resource block mapper 405 .
- An output z of the precoder 404 may be obtained by multiplying output y of the layer mapper 403 by an NxM precoding matrix W.
- N is the number of antenna ports
- M is the number of layers.
- the resource block mapper 405 maps complex-valued modulation symbols for respective antenna ports to appropriate resource elements in a virtual resource block allocated for transmission.
- the resource block mapper 405 may allocate the complex-valued modulation symbols to appropriate subcarriers and multiplex the same according to a user.
- the signal generator 406 may modulate the complex-valued modulation symbols according to a specific modulation scheme, for example, OFDM to generate a complex-valued time domain OFDM symbol signal.
- the signal generator 406 may perform inverse fast Fourier transform (IFFT) on the antenna-specific symbols, and a cyclic prefix (CP) may be inserted into time domain symbols on which IFFT has been performed.
- OFDM symbols are subjected to digital-to-analog conversion, frequency up-conversion, and the like and transmitted to a reception device through respective transmission antennas.
- the signal generator 406 may include an IFFT module, a CP insertion device, a digital-to-analog converter (DAC), a frequency uplink converter, and the like.
- DAC digital-to-analog converter
- a signal processing procedure of a reception device 1820 may be reverse to the signal processing procedure of the transmission device.
- the processor 1821 of the transmission device 10 decodes and modulates a radio signal received from the outside through antenna ports of the transceiver 1822 .
- the reception device 1820 may include multiple reception antennas, and signals received through the reception antennas are restored into baseband signals and then restored into data strings intended to be transmitted by the transmission device 10 through multiplexing and MIMO demodulation.
- the reception device 1820 may include a signal restoration device for restoring a received signal into a baseband signal, a multiplexer for combining and multiplexing received signals, and a channel demodulator for demodulating multiplexed signal strings into corresponding codewords.
- the signal restoration device, the multiplexer, and the channel demodulator may be configured as an integrated module for executing functions thereof or as independent modules. More specifically, the signal restoration device may include an analog-to-digital converter (ADC) for converting an analog signal into a digital signal, a CP remover for removing a CP from the digital signal, an FFT module for applying fast Fourier transform (FFT) to the CP-removed signal to output frequency domain symbols, and a resource element demapper/equalizer for restoring the frequency domain symbols into antenna-specific symbols.
- ADC analog-to-digital converter
- FFT fast Fourier transform
- the antenna-specific symbols are restored into a transport layer through the multiplexer, and the transport layer is restored into a codeword intended to be transmitted by the transmission device through the channel demodulator.
- FIG. 22 shows an example of a wireless communication device according to an implementation example of the present disclosure.
- the wireless communication device for example, a UE may include at least one of a processor 2310 such as a digital signal processor (DSP) or a microprocessor, a transceiver 2335 , a power management module 2305 , an antenna 2340 , a battery 2355 , a display 2315 , a keypad 2320 , a global positioning system (GPS) chip 2360 , a sensor 2365 , a memory 2330 , a subscriber identification module (SIM) card 2325 , a speaker 2345 , and a microphone 2350 .
- a processor 2310 such as a digital signal processor (DSP) or a microprocessor
- DSP digital signal processor
- a transceiver 2335 such as a digital signal processor (DSP) or a microprocessor
- a transceiver 2335 such as a digital signal processor (DSP) or a microprocessor
- a power management module 2305 such as a digital signal processor (DSP) or a micro
- the processor 2310 may implement functions, procedures, and methods described in the present specification.
- the processor 2310 of FIG. 21 may be the processors 1811 and 1821 of FIG. 19 .
- the memory 2330 is connected to the processor 2310 and stores information related to operation of the processor.
- the memory may be located inside or outside the processor and connected to the processor through various techniques such as wired connection and wireless connection.
- the memory 2330 of FIG. 21 may be the memories 1813 and 1823 of FIG. 19 .
- a user may input various types of information such as telephone numbers using various techniques such as pressing buttons of the keypad 2320 and activating sound using the microphone 2350 .
- the processor 2310 may receive user information, process the user information, and execute an appropriate function such as making a call using an input telephone number.
- data may be retrieved from the SIM card 2325 or the memory 2330 in order to execute an appropriate function.
- the processor 2310 may display various types of information and data on the display 2315 for user convenience.
- the transceiver 2335 is connected to the processor 2310 and transmit/receive radio signals such as radio frequency (RF) signals.
- the processor may control the transceiver in order to start communication or transmit radio signals including various types of information or data such as audio communication data.
- the transceiver includes a transmitter and a receiver for transmitting and receiving radio signals.
- the antenna 2340 may facilitate transmission and reception of radio signals.
- the transceiver may forward and convert the signal into a baseband frequency for processing by the processor.
- the processed signal may be processed through various techniques such as conversion into audible or readable information such that it is output through the speaker 2345 .
- the transceiver of FIG. 21 may be the transceivers 1812 and 1822 of FIG. 19 .
- the UE may additionally include various components such as a camera and a universal serial bus (USB) port.
- the camera may be connected to the processor 2310 .
- FIG. 22 is only one implementation example for the UE, and the implementation example is not limited thereto. It is not necessary for the UE to include all components of FIG. 22 . That is, some components, for example, the keypad 2320 , the GSP chip 2360 , the sensor 2365 , and the SIM card may not be essential components, and in this case, they may not be included in the UE.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11272540B2 (en) * | 2018-08-09 | 2022-03-08 | Ofinno, Llc | Channel access and uplink switching |
US11272539B2 (en) * | 2018-08-09 | 2022-03-08 | Ofinno, Llc | Channel access and bandwidth part switching |
Families Citing this family (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2733418C1 (ru) | 2017-03-24 | 2020-10-01 | Телефонактиеболагет Лм Эрикссон (Пабл) | Множество начальных и конечных позиций при запланированной передаче по нисходящей линии связи в нелицензированном спектре |
CN108633046B (zh) * | 2017-03-24 | 2023-08-22 | 华为技术有限公司 | 传输信号的方法和装置 |
US11184924B2 (en) * | 2017-04-28 | 2021-11-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Multiple starting positions for uplink transmission on unlicensed spectrum |
JP7227263B2 (ja) * | 2018-02-14 | 2023-02-21 | アイディーエーシー ホールディングス インコーポレイテッド | ライセンスされていない帯域におけるnew radio(nr)動作のための複数のアンテナ技術を使用する方法、装置、およびシステム |
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US11323989B2 (en) * | 2018-02-26 | 2022-05-03 | Huawei Technologies Co., Ltd. | Method and apparatus for bandwidth indication in unlicensed spectrum |
JP2021520737A (ja) * | 2018-04-06 | 2021-08-19 | ノキア テクノロジーズ オサケユイチア | ライセンスされない新無線でのアップリンク帯域幅部分切替え |
CN110474753A (zh) * | 2018-05-10 | 2019-11-19 | 北京三星通信技术研究有限公司 | 用于数据传输的方法与设备 |
US11848878B2 (en) * | 2018-05-11 | 2023-12-19 | Mediatek Inc. | BWP operation in NR-based unlicensed spectrum |
WO2019246084A1 (en) * | 2018-06-19 | 2019-12-26 | Idac Holdings, Inc. | Radio link monitoring in shared spectrum |
KR20210040036A (ko) * | 2018-08-06 | 2021-04-12 | 삼성전자주식회사 | 비면허 대역들에서 셀 및 대역폭 파트 동작들 |
WO2020029281A1 (zh) * | 2018-08-10 | 2020-02-13 | 富士通株式会社 | 竞争窗口调整方法、装置以及通信*** |
US20210297193A1 (en) * | 2018-08-10 | 2021-09-23 | Wilus Institute Of Standards And Technology Inc. | Method, device, and system for channel access in unlicensed band |
TWI710227B (zh) * | 2018-08-17 | 2020-11-11 | 美商Idac控股公司 | 多trp之波束管理 |
US11438846B2 (en) * | 2018-08-20 | 2022-09-06 | Qualcomm Incorporated | Solutions to handle mis-alignment between radio access technologies (RATs) in dual connectivity (DC) |
CN112586080A (zh) | 2018-09-20 | 2021-03-30 | 谷歌有限责任公司 | 在带宽部分上执行先听后说过程 |
WO2020060361A1 (ko) * | 2018-09-21 | 2020-03-26 | 엘지전자 주식회사 | 비면허 대역에서 단말의 채널 접속 방법 및 상기 방법을 이용하는 장치 |
EP3629505A1 (en) * | 2018-09-25 | 2020-04-01 | Panasonic Intellectual Property Corporation of America | User equipment and base station involved in transmission of data |
CN117042195A (zh) * | 2018-09-27 | 2023-11-10 | 中兴通讯股份有限公司 | 竞争窗的调整方法及装置、存储介质、电子装置 |
US11291046B2 (en) * | 2018-10-18 | 2022-03-29 | Qualcomm Incorporated | Procedures for autonomous uplink transmissions |
CN111525995B (zh) * | 2019-02-03 | 2022-03-29 | 华为技术有限公司 | 一种数据传输方法、网络设备和终端设备 |
CN113228810A (zh) * | 2019-03-21 | 2021-08-06 | 苹果公司 | 基于代码块组的重传配置的竞争窗口大小更新 |
KR20200114224A (ko) * | 2019-03-28 | 2020-10-07 | 삼성전자주식회사 | 비면허 대역을 활용하는 무선통신시스템에서 상향링크 LBT (Listen-Before-Talk) 실패를 감지하는 방법 및 장치 |
US11329769B2 (en) * | 2019-08-01 | 2022-05-10 | Qualcomm Incorporated | Techniques for contention window adjustment |
EP4014663A4 (en) * | 2019-08-13 | 2023-04-19 | Nokia Technologies Oy | PROCEDURE FOR ACCESSING A CHANNEL ACCORDING TO A CHANNEL ACCESS PRIORITY CLASS |
CN112654096A (zh) * | 2019-10-11 | 2021-04-13 | 普天信息技术有限公司 | 竞争窗长度自适应调整方法和装置 |
CN113709897A (zh) * | 2020-05-21 | 2021-11-26 | 索尼公司 | 用于无线通信的电子设备和方法、计算机可读存储介质 |
US11582800B2 (en) * | 2021-01-07 | 2023-02-14 | Qualcomm Incorporated | Contention window adjustment for group channel occupancy time sharing |
CN116941309A (zh) * | 2021-03-10 | 2023-10-24 | Oppo广东移动通信有限公司 | 无线通信方法和第一设备 |
US20220295549A1 (en) * | 2021-03-12 | 2022-09-15 | Qualcomm Incorporated | Listen-before-talk techniques for full-duplex communications |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016182356A1 (ko) | 2015-05-12 | 2016-11-17 | 엘지전자 주식회사 | 비면허 대역을 지원하는 무선접속시스템에서 서로 다른 타입의 신호를 전송하기 위한 채널 접속 과정을 수행하는 방법 및 장치 |
WO2017030417A1 (ko) | 2015-08-20 | 2017-02-23 | 엘지전자 주식회사 | 비면허 대역을 지원하는 무선접속시스템에서 경쟁윈도우크기를 조정하는 방법 및 장치 |
US20170055296A1 (en) | 2015-03-17 | 2017-02-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Communication device and a method therein for determining a contention window size in a communication network |
US20170086225A1 (en) * | 2015-09-23 | 2017-03-23 | Sony Mobile Communications Inc. | Contention window adjustment in unlicensed cellular radio network |
US20170142751A1 (en) | 2015-11-13 | 2017-05-18 | Futurewei Technologies, Inc. | Device, Network, and Method for Communications with Opportunistic Transmission and Reception |
US20190045489A1 (en) * | 2017-09-11 | 2019-02-07 | Hong He | Hybrid automatic repeat request (harq) based on codeblock groups in new radio systems |
US10206223B2 (en) * | 2015-02-06 | 2019-02-12 | Apple Inc. | Method and apparatus for time division LTE transmission in unlicensed radio frequency bands |
US20200059327A1 (en) * | 2017-05-03 | 2020-02-20 | Idac Holdings, Inc. | METHOD AND APPARATUS FOR IMPROVING HYBRID AUTOMATIC REPEAT REQUEST (HARQ) FEEDBACK PERFORMANCE OF ENHANCED MOBILE BROADBAND (eMBB) WHEN IMPACTED BY LOW LATENCY TRAFFIC |
US20200236709A1 (en) * | 2017-08-02 | 2020-07-23 | Lg Electronics Inc. | Method for transmitting, by base station, downlink signal in wireless communication system supporting unlicensed band and device for supporting same |
US20200374933A1 (en) * | 2018-01-10 | 2020-11-26 | Idac Holdings, Inc. | Data transmissions and harq-ack associated with an unlicensed spectrum |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9301319B2 (en) * | 2013-01-14 | 2016-03-29 | Qualcomm Incorporated | Systems and methods for modifying carrier sense multiple access (CSMA) for dense networks |
US10742562B2 (en) * | 2015-07-16 | 2020-08-11 | Samsung Electronics Co., Ltd. | Method and apparatus for adaptive control of contention window in LAA |
US9992785B2 (en) * | 2015-11-14 | 2018-06-05 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Adjusting transmission parameters to support coexistence fairness |
BR112018070174A2 (pt) * | 2016-03-31 | 2019-01-29 | Huawei Tech Co Ltd | método e aparelho para determinar o tamanho da janela de contenção na avaliação do canal claro |
-
2019
- 2019-02-12 EP EP19751788.1A patent/EP3726919B1/en active Active
- 2019-02-12 WO PCT/KR2019/001711 patent/WO2019156542A1/ko unknown
- 2019-02-12 CN CN201980009098.8A patent/CN111630932B/zh active Active
- 2019-02-12 CN CN202311100721.5A patent/CN116915376A/zh active Pending
-
2020
- 2020-07-09 US US16/924,626 patent/US11122632B2/en active Active
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10206223B2 (en) * | 2015-02-06 | 2019-02-12 | Apple Inc. | Method and apparatus for time division LTE transmission in unlicensed radio frequency bands |
US20170055296A1 (en) | 2015-03-17 | 2017-02-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Communication device and a method therein for determining a contention window size in a communication network |
WO2016182356A1 (ko) | 2015-05-12 | 2016-11-17 | 엘지전자 주식회사 | 비면허 대역을 지원하는 무선접속시스템에서 서로 다른 타입의 신호를 전송하기 위한 채널 접속 과정을 수행하는 방법 및 장치 |
US20180115981A1 (en) | 2015-05-12 | 2018-04-26 | Lg Electronics Inc. | Method and device for performing channel access process for transmitting different types of signals in wireless access system supporting unlicensed band |
WO2017030417A1 (ko) | 2015-08-20 | 2017-02-23 | 엘지전자 주식회사 | 비면허 대역을 지원하는 무선접속시스템에서 경쟁윈도우크기를 조정하는 방법 및 장치 |
US20170086225A1 (en) * | 2015-09-23 | 2017-03-23 | Sony Mobile Communications Inc. | Contention window adjustment in unlicensed cellular radio network |
US20170142751A1 (en) | 2015-11-13 | 2017-05-18 | Futurewei Technologies, Inc. | Device, Network, and Method for Communications with Opportunistic Transmission and Reception |
US20200296761A1 (en) * | 2015-11-13 | 2020-09-17 | Futurewei Technologies, Inc. | Device, Network, and Method for Communications with Opportunistic Transmission and Reception |
US20200059327A1 (en) * | 2017-05-03 | 2020-02-20 | Idac Holdings, Inc. | METHOD AND APPARATUS FOR IMPROVING HYBRID AUTOMATIC REPEAT REQUEST (HARQ) FEEDBACK PERFORMANCE OF ENHANCED MOBILE BROADBAND (eMBB) WHEN IMPACTED BY LOW LATENCY TRAFFIC |
US20200236709A1 (en) * | 2017-08-02 | 2020-07-23 | Lg Electronics Inc. | Method for transmitting, by base station, downlink signal in wireless communication system supporting unlicensed band and device for supporting same |
US20190045489A1 (en) * | 2017-09-11 | 2019-02-07 | Hong He | Hybrid automatic repeat request (harq) based on codeblock groups in new radio systems |
US20200374933A1 (en) * | 2018-01-10 | 2020-11-26 | Idac Holdings, Inc. | Data transmissions and harq-ack associated with an unlicensed spectrum |
Non-Patent Citations (6)
Title |
---|
Extended European Search Report in EP Appln. No. 19751788.1, dated Dec. 22, 2020, 9 pages. |
Huawei, HiSilicon, Autonomous uplink access on LBT, R2-1708892, 3GPP TSG-RAN2 Meeting #99, Berlin, Germany, Aug. 21-25, 2017, 3 pages. |
Huawei, HiSilicon, Contention window size adjustment for UL category 4 LBT for eLAA, R1-164073, 3GPP TSG RAN WG1 Meeting #85, Nanjing, China, May 23-27, 2016, 4 pages. |
LG Electronics, "Channel access procedure for NR-U," R1-1900606, 3GPP TSG RAN WG1 Ad-Hoc Meeting 1901, Taipei, Taiwan, Jan. 21-25, 2019, 11 pages. |
LG Electronics, Channel access procedure for autonomous UL access, R1-1719865, 3GPP TSG RAN WG1 Meeting 91, Reno, USA, Nov. 27-Dec. 1, 2017, 6 pages. |
Samsung, SI Reception in RRC Connected: Bandwidth Part Aspects, R2-1710092, 3GPP TSG-RAN WG2 #99bis, Prague, Czech Republic, Oct. 9-13, 2017, 3 pages. |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11272540B2 (en) * | 2018-08-09 | 2022-03-08 | Ofinno, Llc | Channel access and uplink switching |
US11272539B2 (en) * | 2018-08-09 | 2022-03-08 | Ofinno, Llc | Channel access and bandwidth part switching |
US11638301B2 (en) | 2018-08-09 | 2023-04-25 | Ofinno, Llc | Listen before talk procedure and bandwidth part switching |
US11743942B2 (en) | 2018-08-09 | 2023-08-29 | Ofinno, Llc | Listen before talk procedure and uplink switching |
US11930531B2 (en) | 2018-08-09 | 2024-03-12 | Ofinno, Llc | Consecutive listen-before-talk procedures based on bandwidth part switching |
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WO2019156542A1 (ko) | 2019-08-15 |
US20200344819A1 (en) | 2020-10-29 |
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